Fuel injection system



y 28, 1957 B. B. FLOYD 2,793,628

FUEL INJECTION SYSTEM Filed Sept. 7, 1955 -3 Sheets-Sheet l Fig./

Baron B. Floyd INVENTOR.

BY V w v May 28, 1957 Filed Sept. 7, 1955 B. B. FLOYD FUEL INJECTION SYSTEM 3 Sheets-Sheet 2 Baron B. Floyd INVENTOR.

BII/

y 7 B. B.,FLOYD 2,793,628

' FUEL INJECTION SYSTEM FiledSept. 7, 1955 3 Sheets-Sheet 5 Fig.4

Baron B. lo yd INVENTOR.

' 9 BY wbu fi% FUEL INJECTION SYSTEM Baron B. Floyd, Houston, Tex.

Application September 7, 1955, Serial No. 532,838

Claims. (Cl. 123-48) This invention relates in general to new and useful improvements in internal combustion engines, and more specifically to an improved fuel injection system for internal combustion engines.

Fuel injectors for gasoline and diesel engines have, in the past, been unsatisfactory and expensive due to mechanical difficulties incurred in injecting the exact amount of fuel to obtain the correct air-fuel mixture in the cylinders of such engines. As the engine revolution increases, the amount of air drawn into each cylinder diminishes. Similarly, the amount of air decreases with a change in atmospheric pressure. This has, in the past involved the use of many delicate and expensive pumps and fuel regulators which, for the most part, have proved to be not feasible from an economic standpoint.

It is therefore the primary object of this invention to provide an improved fuel injection system which relies upon the pressure within the individual cylinders of an engine for controlling the injection of such fuel.

Another object of this invention is to provide an improved injection system which is self-contained and which is of such a nature whereby it may be adapted to existent types of internal combustion engines by making changes in construction of the head alone.

Another object of this invention is to provide .an improved fuel injection system which is so constructed whereby the amount of fuel metered from the fuel pump may be easily controlled externally of the pump.

A further object of this invention is to provide an improved fuel injection system which is primarily intended to be mounted in a head of an internal combustion engine, the fuel injection system being of such a nature whereby all of the components thereof may be installed on the head with a major portion thereof mounted entirely within the head.

A still further object of this invention is to provide an improved fuel injection system which is operated by the compression developed in the individual cylinders of an internal combustion engine, the entire fuel injection system being protected and actuated by a valve mounted in a protective position with respect to the various elements of the fuel injection system.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout and in which:

Figure l is a fragmentary vertical sectional view taken through one cylinder of an internal combustion engine and shows the general details of a major portion of the fuel injection system including a fuel pump and the valve assembly, there also being illustrated the details of a distributor for controlling the actuation of the valve;

Figure l-A is a fragmentary vertical sectional view taken through another cylinder of the engine of Figure l and shows the relationship of the fuel injection sysnited tates Patent 0 tem of Figure 1 with respect to an intake manifold pas sage of the second cylinder;

Figure 2 is a fragmentary vertical sectional view similar to Figure 1 showing the fuel injection system in an operative position;

Figure 2-A is a fragmentary vertical sectional view similar to Figure 1-A and shows the fuel being injected into the intake manifold passage;

Figure 3 is a fragmentary vertical sectional view taken through an internal combustion engine and shows a modifiedform of fuel injection system; and

Figure 4 is a fragmentary vertical sectional view similar to Figure 3 and shows the fuel injection system in operation.

Referring now to the drawings in detail, it will be seen that there is illustrated a conventional type of internal combustion engine which is referred to in general by the reference numeral 10. The internal combustion engine 10 includes a block 12 which has formed therein a plurality of cylinders including a cylinder 14. Mounted in the cylinder 14 is a piston 16. Closing the upper end of the cylinder 14 and resting upon the block 12 is a cylinder head 18.

As is best illustrated in Figure 1A, the internal combustion engine 10 also includes a second cylinder 20 having a piston 22 mounted therein for reciprocation. The cylinder head 18 or a separate cylinder head in the case of a V-type engine closes the upper end of the cylinder 20. The cylinder head 18 is provided with an intake passage 24 which opens into the upper end of the cylinder 20 and which is closed by an intake valve 26. Connected to the head 18 is an intake manifold 28 having an intake passage 30 aligned with the intake passage 24.

The head 18 is provided in alignment with each of the cylinders in the block 12 with an internally threaded bore 32. Removably engaged with the internally threaded bore 32 is the reduced externally threaded portion 34 of a plug which is referred to in general by the reference numeral 36. The plug 36 forms a major component of the fuel injection system, which is referred to in general by reference numeral 38, inasmuch as it carries substantially all of the operating elements thereof.

Formed in the lower part of the plug 36 and communicating with the interior of the cylinder 14 is a port 40. Surrounding the port 40 at the lower end thereof is a valve seat 42 which is engaged by a valve head 44 to close the port 40. The valve head 44 forms a part of a valve, which is referred to in general by the reference numeral 46. The valve 46 also includes a valve stem 48 which is connected to a valve head 44.

Formed in the plug 36 and centered with respect to the valve seat 42 is a bore 50 which functions as a valve guide for the valve stem 48. The valve stem 48 is mounted within the bore 50 for reciprocation so that the valve 46 may be moved between open and closed positions.

Also formed in the plug 36 is a cylinder 52. The cylinder 52 opens through the lower part of the plug 36 into the port 40. Aligned with the cylinder 52 and extending upwardly from the upper surface of the plug 56 is an externally threaded extension 54. The extension 54 has a small bore 56 therethrough, the bore 56 communicating with the upper end of the cylinder 52.

Formed in the upper part of the plug 36 is a transverse bore 58 which is communicated with the upper part of the cylinder 52. The bore 58 includes an enlarged outer portion 60 which is externally threaded. Threadedly eugaged in the enlarged outer portion 60 is a fuel line connection 62 of the type including an internal check valve. Connected to the fitting 62 is a fuel supply line 64.

Communicated with the cylinder 52 on the :side thereof opposite from the bore 58 is a fuel discharge passage 66. The fuel discharge passage 66 intersects the lower part of the bore 50 and opens through a side of the plug 36. Connected to the plug 36 in alignment with the fuel discharge passage 66 is an external fuel line 68, the fuel line 68 being communicated with the fuel discharge passage 66 by means of a fitting 7 0.

Mounted within the cylinder 52 and forming together with the cylinder 52 a fuel pump, which is referred to in general by the reference numeral 72, is a piston 74. The piston 74 is retained against removal from the bottom of the cylinder 52 by means of a locking ring 76 carried by the Walls of the cylinder 52. Normally urging the piston 74 downwardly is a coil spring 78 which is mounted in the upper part of the cylinder 52 and which bears against the upper end of the piston 76.

In order that the tension of the spring 78 on the piston 74 may be varied, there is provided an adjustable stop member 80 which projects up into the bore '56. The extension 54 is provided with a cap 82 having a pin portion 84 which extends down into the bore 54 and engages the upper part of the stop '80. By adjusting the cap 82, the stop 80 may be moved up and down, as desired, to vary the position and tension of the spring 78.

The plug 36 also includes a vent passage 86. The vent passage 86 extends between the port 40 in the exterior of the plug 36 to vent the port 40 as desired. The vent passage '86 intersects the bore 50 above the intersection of the fuel discharge passage 66 therewith.

The plug 36 includes an externally threaded portion 88 through which the valve stem 48 passes. Remov- -ably engaged on the portion 88 is an electromagnetic device 90 having a plunger 92 which is engaged with the upper end of the valve stem 48. Operation of the plunger 92 is caused by energization of a coil 94 of the electromagnetic device 90. The plunger 92 is normally urged upwardly by means of the coil spring 96 forming a part of the electromagnetic device 90.

In order to effect the timed operation of the electromagnetic device 90, there is provided a distributor which is referred to in general by the reference numeral 98; .The distributor 98 includes a shaft 100 which is conneoted to the drive train of the internal combustion engine in any conventional manner. Carried by the shaft 100 is a rotor 102. The rotor 102 includes a removable contact 104 engageable with fixed contacts 106. Extending between each of the fixed contacts 106, there being one contact 106 for each cylinder of the internal combustion engine 10, and its associated electromagnetic device 90 is a wire 108.

Referring now to Figure 1-A in particular, it will be seen that the external fuel line 6 8 is connected to that portion of the intake manifold 28 for the cylinder by means of a fitting 110. The fitting 110 terminates in an injection nozzle 112 which projects into the intake passage 30. Also mounted in the intake passage are suitable butterfly valves 114 and 116 for controlling the flow of air through the intake passage 30. The butterfly valve 114 has connected thereto a throttle control member 118 while the butterfly valve 116 has connected thereto a choke control 120.

Referring now to Figures 1, l-A, 2 and 2-A, it will be seen that when the piston 16 is on its compression stroke, the piston 22 is on its intake stroke. As is best illustrated in Figure 2, the distributor 98 is so timed that prior to the reaching of the upper end of its compression stroke by the piston 16, the valve 46 is actuated by energizing the electromagnetic device 90. As the valve 46 moves to an open position, the port is communicated with the interior of the cylinder 14.. At the same time, a relief passage 122 formed in the valve stem 48 intermediate the ends thereof moves into alignment with the fuel discharge passage 66. The communication of theport 40 with the cylinder.14 during the compression The upward movement of the piston 76 will result in the pumping of the fuel disposed in the upper part of the cylinder 52 out through the fuel discharge passage 66 due to the provision of the check valve in the fitting 62. This results in the fuel being pumped to the fuel passage 68 and out through the injection nozzle 112. The fuel injected into the intake manifold 28 through the nozzle 112 will combine with the air passing through the intake manifold 28 so that the proper fuel-air mixture will be present in the cylinder 20.

From the foregoing, it will be readily apparent that once the spring 78 has been properly adjusted by means of the cap 82, the proper amount of fuel will be injected in each of the cylinders of the internal combustion engine 10 upon the operation of the valve 46 for the particular portion of the fuel injection system 38. This is due to the controlling of the pump 72 by the compression within its associated cylinder.

It is pointed out at this time that each cylinder of the internal combustion engine '10 will be provided with one of the plugs 36 and its component parts. Likewise, each cylinder of the internal combustion engine 10 will have associated therewith either a separate intake manifold, such as the intake manifold 28, or portions of a similar manifold. Thus, each of the cylinders of the internal combustion engine 10 will have its fuel supply injected thereinto with such fuel supply being controlled by the pressure within a companion cylinder of the internal combustion engine 10 and timed by means of the distributors 98.

Referring now to Figures 3 and 4, it will be seen that there is illustrated a modified form of fuel injection system which is referred to in general by the reference numeral 124. Inasmuch as the fuel injection system 124 is identical with the fuel injection system 38 only with the exception of the change in the arrangement of a fuel discharge passage and the position of the nozzle therefor, only those portions of the fuel injection system 124 which differ from the fuel injection system 38 will be described in detail.

The fuel injection system 124 includes a plug which is referred to in general by the reference numeral 126. The plug 126 differs from the plug 36 only in the configuration of a fuel discharge passage 128 thereof. In lieu of passing through the wall of the plug 126 as in the case of the fuel discharge passage 66, the fuel discharge passage 128 opens down into the port 40 and terminates in an injection nozzle 130 disposed at one side of the port 40.

Also, the plug 126 includes a cylinder 132 which has a reduced upper portion 134. Mounted in the lower part of the cylinder 132 is a piston 136 having a reduced upper portion 138 disposed in the reduced portion 134 of the cylinder 132. A fuel supply line 64 is communicated with the upper reduced portion 134 by means of the fitting 62. Further, the fuel discharge passage 128 is communicated with the reduced upper portion 134.

Mounted within the reduced upper portion 134 of the cylinder 132 is a coil spring 140 which is similar to the coil spring 78, but is of a reduced size. Positioning of the coil spring 140 is controlled by means of the cap 82 and the stop 80.

The operation of the fuel injection system 124 is controlled by a valve 46 for each cylinder of the internal combustion engine 10, the valve being actuated by the electromagnetic device 90.

In the operation of the fuel injection system 124, as the piston 16 of the particular cylinder 14 appoaches the upper end of its compression stroke, the electromagnetic device 90 is actuated by the distributor 98 to result in the opening of the valve 46. As the valve 46 moves to its open position, its relief passage 122 becomes aligned with the fuel discharge passage 128. Similarly, the compression from within the cylinder 14 enters into the port 40 and causes upward movement of the piston 136. The

upper portion 138 of the piston 136 moves upwardly in the reduced upper portion 134 of the cylinder 132 to cause pumping of the fuel disposed within the upper portion 134 out through the fuel discharge passage 128. Because of the differential in size between the upper and lower portions of the piston 136, there will be sufficient pressure on the fuel passing through the fuel discharge passage 128 to be injected into the cylinder 12 through the nozzle 130. Inasmuch as the nozzle 130 is disposed at one side of the port 40, the head 44 of the valve 46 moves to an open position, it will move out of alignment with the nozzle 130 and permit the spraying of fuel into the cylinder 12 above the piston 16.

When the circuit to electromagnetic device 90 is broken, the spring 96 thereof will urge the valve 46, which is connected to the plunger 92 upwardly to its closed position. At this time, gases will be trapped in the port 40 under pressure. In order to vent the port 40, the relief passage 122 is communicated with the vent passage 86 in the closed position of the valve 46, as is best illustrated in Figure 3. This is also true of the fuel injection system 38 and is best illustrated in Figure 1.

-It is to be understood that the fuel injection systems 38 and 124 are adaptable to all types of internal combustion engines. The engines will be changed only as necessary to modify the heads or other portions thereof to receive the fuel injection systems. If desired, the plugs 3,6 and 126 may be conveniently threaded into parts of the block of the internal combustion engine. Further, the plugs 36 and 126 may be omitted and the heads or blocks of internal combustion engines configurated in the same manner as the plugs 36 and 126 to receive the components of the fuel injection systems 38 and 124.

It is to be understood that the internal combustion engines provided with the fuel injection systems 38 and 124 will not be modified other than the adaptation of the fuel injection systems thereto. The engines will be provided with the customary intake and exhaust valves and will operate on the same timing. Further, in the event the particular internal combustion engine is of a type primarily intended for use in burning gasoline, there will be provided the usual ignition system including the spark plugs. On the other hand, should the internal combustion engine be of the diesel type, the injection period will be so timed as to cause firing of the fuel-air mixture upon the injection of the fuel. It will be apparent that the form of the invention illustrated in Figures 3 and 4 will be best adapted for use in conjunction with diesel engines.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In combination with a cylinder head, a port in the cylinder portion of said head, a valve seat surrounding said port, a valve having a valve head engaging said valve seat to close said port, a pressure actuated fuel pump formed in said head and communicated with said port, and means for periodically moving said valve to an open position, said valve having a valve stem guidedly retained in said head, a fuel discharge passage from said pump in said head, said fuel discharge passage intersecting said valve stem, a relief passage in said valve stem alignable with said fuel discharge passage to permit fuel flow therethrough.

2. In combination with a cylinder head, a port in the cylinder portion of said head, a valve seat surrounding said port, a valve having a valve head engaging said valve seat to close said port, a pressure actuated fuel pump formed in said head and communicated with said port for actuation by gases entering said port under pressure, a fuel inlet passage and a fuel discharge passage connected to said pump, and means for periodically moving said valve to an open position, said valve having a valve stem guidedly retained in said head, a vent passage in said head between said port and the exterior of said head for relieving the pressure in said port when said valve is closed, said vent passage intersecting said valve stem, a relief passage in said valve stem alignable with said vent passage to permit venting of said port.

3. In combination with a cylinder head, a port in the cylinder portion of said head, a valve seat surrounding said port, a valve having a valve head engaging said valve seat to close said port, a pressure actuated fuel pump formed in said head and communicated with said port for actuation by gases entering said port under pressure, and means for periodically moving said valve to an open position, said valve having a valve stem guidedly retained in said head, a fuel discharge passage from said pump in said head, said fuel discharge passage intersecting said valve stem, a vent passage in said head between said port and the exterior of said head for relieving the pressure in said port when said valve is closed, said vent passage intersecting said valve stem, a relief passage in said valve stem selectively alignable with said fuel discharge passage and said vent passage.

4. In combination with a cylinder head, a port in the cylinder portion of said head, a valve seat surrounding said port, a valve having a valve head engaging said valve seat to close said port, a pressure actuated fuel pump formed in said head and communicated with said port for actuation of gases entering said port under pressure, and means for periodically moving said valve to an open position, said valve having a valve stem guidedly retained in said head, a fuel discharge passage from said pump in said head, said fuel discharge passage intersecting said valve stem, a vent passage in said head between said port and the exterior of said head for relieving the pressure in said port when said valve is closed, said vent passage intersecting said valve stem, a relief passage in said valve stem selectively alignable with said fuel discharge passage and said vent passage, said fuel discharge passage and said vent passage being so spaced whereby said relief passage is aligned with said fuel discharge passage when said valve is open, and with said vent passage when said valve is closed.

5. In combination with a cylinder head, a port in the cylinder portion of said head, a valve seat surrounding said port, a valve having a valve head engaging said valve seat to close said port, a pressure actuated fuel pump formed in said head and communicated with said port, and means for periodically moving said valve to an open position, said valve having a valve stem guidedly retained in said head, a fuel discharge passage from said pump in said head, said fuel discharge passage intersecting said valve stem, a relief passage in said valve stem alignable with said fuel discharge passage to permit fuel flow therethrough, said fuel discharge passage terminating in a discharge nozzle, said discharge nozzle being positioned in said port.

References Cited in the file of this patent UNITED STATES PATENTS 1,376,277 Higgins Apr. 26, 1921 FOREIGN PATENTS 443,427 France July 13, 1912 1,007,984 France Feb. 13, 1952 497,163 Germany May 3, 1930 

